As is known in the art, prior to shipping a computer product to a consumer the computer product typically undergoes a series of tests. The tests generally include diagnostic tests, environmental tests and mechanical tests. The diagnostic tests verify that the computer product is capable of performing each of its purported functions at an expected performance. The environmental tests are performed to ensure that the computer product can perform as expected in the presence of certain environmental conditions, such as extreme temperatures or moisture. The mechanical tests are performed to ensure that the computer product can perform as expected under the application of physical stress. Mechanical tests may include, for example, shock and vibration testing, bump testing or low pressure testing.
During mechanical and environmental testing, the computer product typically executes a set of diagnostic tests while under the environmental or mechanical stresses. Should the computer product fail to pass the diagnostics during these tests, it will not be forwarded to the consumer but rather will be set aside for evaluation and repair.
Many computer system products are generally formed from a number of components that are interconnected via a backplane. Often the backplane is housed in an enclosure, which has a number of interconnects, or slots, for linking the system components to the backplane. In the specification, ‘enclosure’ is meant to be any type of structure that includes component connectors, and is not limited to enclosed devices. Before a system is shipped both the components and the enclosure must undergo test.
A company can use a common enclosure design to provide a wide range of systems having different capabilities by populating the slots of the enclosure with different numbers and types of components. Such an arrangement allows a consumer to purchase a lower end system, and subsequently upgrade the system by adding components empty slots as the consumers need for capacity and performance increases. Even though an enclosure may be sold to the consumer as part of a partially populated system, it is important that each of the slots of the enclosure be verified as operational so that later upgrades to the system may be performed seamlessly. Therefore the systems are generally tested at full capacity; i.e. as a fully populated enclosure.
Because it is desirable to fully populate an enclosure for testing purposes, an inventory of extra components is maintained in the test lab. Often only a portion of the components that are used to test an enclosure are shipped with the enclosure, while the remaining components are returned to the inventory and used for subsequent tests. It may occur that a given component goes through a testing process numerous times in the process of enclosure testing.
The frequent re-use of components in the enclosure design process may place a significant amount of wear and tear on a component as they are swapped into and out of the enclosure. The added wear and tear may undesirably decrease the available life span of the product before it is shipped to a consumer.
As the component cost and complexity increases, the wear and tear placed on the components may cause the components to become inoperable, and unavailable for shipping with a product. For example rotating magnetic media, such as disk drives, are delicate and may be damaged if pulled out of an enclosure and placed on a bench when the magnetic heads are still rotating. In addition, frequent environmental testing of the disk drive component can adversely affect the distance of the fly height of the head over the magnetic medium. If the effects of testing are significant enough to damage the component, then the component must be removed from the inventory of product available for shipment.
Accordingly there is a cost associated with maintaining an inventory of components for full system testing. In addition to the cost associated with individual component loss, the inventory cost is also increased when enclosures are designed to receive complex and expensive components. Each component that may be included in the system needs to be tested in the enclosure. As individual components are upgraded, the enclosure should be tested using the latest version of the component. Thus a variety of components that are not frequently shipped with the enclosure must be maintained in the inventory. For low margin systems, the breadth of the test inventory undesirably reduces an already low profit margin.
It would be desirable to identify a method and apparatus for testing an enclosure that would reduce the total cost associated with the test process and also the wear and tear on system components.